B.C. MEDIUM DEVELOPMENTS. 4000 B.C. Boiled tree sap, called pitch, was distilled into turpentine as a paint thinner for the resin paints. Also, alcohol was fermented as a drink and as a thinner for alcohol based paints, made from another tree sap or grapes.
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John Betts Fine Minerals, New York, NY Dealers of Fine Minerals and Natural Crystal Clusters since 1989. Journal of weekly news and commentaries about rocks and minerals and mineral collecting
Tungsten, or wolfram, is a chemical element with symbol W and atomic number 74. The name tungsten comes from the former Swedish name for the tungstate mineral scheelite, tung sten or "heavy stone". Tungsten is a rare metal found naturally on Earth almost exclusively combined with other elements in chemical compounds rather than alone. It was identified as a new element in 1781 and first
Coltan (short for columbitetantalites and known industrially as tantalite) is a dull black metallic ore, from which the elements niobium and tantalum are extracted. The niobium dominant mineral in coltan is columbite (after niobium's original American name columbium), and the tantalum dominant mineral is tantalite.. Tantalum from coltan is used to manufacture batteries for electric cars